Carbon Dioxide Helps Some Plants Survive Cold Weather, Cornell Researchers Find

Contact: Blaine P. Friedlander, Jr.Office: (607) 255-3290E-mail: bpf2@cornell.edu

ITHACA, N.Y. -- Elevated levels of carbon dioxide in the atmosphere benefitsome plants by making them more tolerant to cold temperatures, CornellUniversity researchers have discovered.

"This could mean earlier spring planting dates for some crops in thefuture," said David Wolfe, Cornell associate professor in the Department ofFruit and Vegetable Science. "It may also affect the mixture of species innatural plant communities, because only certain plants benefit in thisway." The researchers' study, "Elevated carbon dioxide mitigateschilling-induced water stress and photosynthetic reduction duringchilling," was published recently in the journal Plant, Cell andEnvironment (1997 20, 625-632). Steve Boese, instructor at the College ofCharleston, Charleston, S.C., and Jeff Melkonian, Cornell post-doctoralresearcher, co-authored the paper with Wolfe.

Also, Wolfe will present a poster on this topic at the Plant Biology '97conference cosponsored by the American and Canadian Societies of PlantPhysiology, in Vancouver, Canada, on Aug. 3 and 4.

"Our results are another example of how the increase in carbon dioxide andother greenhouse gases will shake up the plant world," Wolfe said. "Ourmaps of global vegetation zones will inevitably be altered by these sortsof direct effects on plants, whether or not we also have major changes inclimate."

The research was supported by the U.S. Department of Agriculture's SpecialGrants Agricultural Ecosystems Program.

The researchers have focused much of their attention thus far on two crops,beans and cucumbers, that are among a class of plants that tend to wiltwhen temperatures dip below about 45 degrees Fahrenheit. They knew fromprior experiments that elev